A Study of Cataclysmic Variables from the eFEDS Survey

TL;DR

This paper reports the discovery and analysis of 17 cataclysmic variables from the eFEDS survey, including period determination and mass estimation, enhancing understanding of these binary systems.

Contribution

It introduces 9 newly identified CVs from eFEDS and confirms their orbital periods and component masses using multi-survey data integration.

Findings

17 CVs identified from eFEDS survey

Orbital periods confirmed for two CVs

White dwarf and star masses constrained

Abstract

We present 17 cataclysmic variables (CVs) obtained from the crossmatch between the Sloan Digital Sky Survey (SDSS) and eROSITA Final Equatorial Depth Survey (eFEDS), including 8 known CVs before eFEDS and 9 identified from eFEDS. The photometric periods of four CVs are derived from the Zwicky Transient Facility (ZTF) and Catalina Real-Time Transient Survey (CRTS). We focus on two CVs, SDSS J084309.3$-$014858 and SDSS J093555.0+042916, and confirm that their photometric periods correspond to the orbital periods by fitting the radial velocity curves. Furthermore, by the combination of the Gaia distance, the spectral energy distribution, and the variations of $\mathrm{H}\mathrm{\alpha}$ emission lines, the masses of the white dwarf and the visible star can be well constrained.